Whew! I started to refactor this but ran into some things I couldn't translate. So I thought I would point out what I found and let you do the work. (Who knows, it might be homework.)

First off, you use the following block over and over. It screams for a subroutine:

$trans[int(rand($#trans + 1))]
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At first I wrote this as a sub called pick:

sub pick
{
  my $aref = shift;
  return $aref->[int(rand(scalar(@$aref)))];
  
}
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Second, rather than having an array for each language element type, I would put this in a hash of arrays (HOA):

my %parts = ( 
             det =>        
             [qw{the a ninety}], #determiner
             pro =>        
             [qw{it I ya theirs}], # pronoun
             properNoun => 
             [qw{Alpesh Ann China Beijing}], # proper noun
             ...
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That way you could access individual items with:

  $parts{adj}->[1]
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And combine this with the pick function I mentioned up above. To pick one word out of any part:

  pick($parts{adj});
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Next a couple of observations. In createNP I ran across a problem. You're using a global variable $randnum to hold a random number:

sub createNP{
  my(@adjp);

  while ((my$counter = 0) < 100)
  {
    $randnum = int(rand(5)+1);        
    if ($randnum == 1)
    {
      $randnum = int(rand(2)+1);
      if ($randnum == 1)
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After looking at it, it looks right, but it would be better if you used a local variable to hold the random value that is used within a local scope. Also the problem with the while loop that was mentioned earlier.

sub createNP{

  my(@adjp);
  my $counter = 0;
  while ($counter < 100)
  {
    my $outerRN = int(rand(5)+1);        
    if ($outerRN == 1)
    {
      my $innerRN = int(rand(2)+1);
      if ($innerRN == 1)
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Finally, I noticed that you are using an array to accumulate results:

$np[$counter] = $pluralNoun[int(rand($#pluralNoun + 1))];
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This can be done without an index by using the push function.

 push(@np , $pluralNoun[int(rand($#pluralNoun + 1))])
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All I've got time for now. HIH.